You may be running with Auto Close Settings which specify the number of end user business hours that have passed before automatic closure of resolved requests, incidents, problems, change orders, and/or issues. What is the basis of the 'business hours'?
The hours are based on an out-of-the-box Workshift named "Regular". The description for this workshift is "Normal Business Hours".
Auto Close Settings and Workshifts can be viewed within the Administration tab. This tab is normally available when running under the Administrator role. To navigate to the corresponding lists, first open the Service Desk folder and, from under that, open the Application Data sub folder. Then, for the list of Auto Close Settings, open the Codes subfolder (see Figure 1) and for the list of Workshifts, open the Workshift subfolder (see Figure 2). Click on "Regular" in the Workshift List to view the details, such as the Schedule (see Figure 3).
Note: The workshifts are stored in the Bop_Workshift table and the Regular workshift has a persid of "wrkshft:4600".
Figure 1. Navigating to the Auto Close Settings List.
Figure 2. Navigating to the Workshift List.
Figure 3. Regular workshift.